Overview of Radial Forearm Tissue Transfer
The Radial Forearm Free Flap (RFFF) is a type of reconstructive surgery that has been popular since it was introduced in 1978. This procedure makes use of tissue from your forearm to repair missing or damaged areas in your head or neck. It is a preferred choice for many surgeons because it is relatively easy to perform, the tissue is flexible, and the structure of the arm is usually consistent from person to person.
This surgery is often used to rebuild parts of the throat and mouth, as well as the passageway for food and air (called the pharyngoesophagus), and the scalp.
Understanding the detailed structure of your forearm is key for this procedure. Knowing when it’s the best choice and when it’s not safe to perform (indications and contraindications) is also crucial. The surgery team must make important decisions before the surgery, during the procedure, and during the recovery period to ensure the best care for the patient.
Anatomy and Physiology of Radial Forearm Tissue Transfer
The radial forearm free flap is a method where a part of the skin, tissue, or bone from the forearm is used to replace or repair other parts of the body. This is a very versatile procedure as it can involve just the tissue (fascial), skin and tissue (fasciocutaneous), or skin, tissue and bone (osteocutaneous). Doctors can even ensure that the transferred tissue retains its sense of touch if necessary.
The typical size of the skin area used in this procedure is about nine centimeters, but the entire skin of the forearm can be used if the situation requires it. The skin area, known as cutaneous paddle, is chosen in relation to the radial artery and two veins accompanying it. These blood vessels are important because they supply blood to the transferred tissue and keep it alive.
These blood vessels are found in a particular area that divides the flexor carpi radialis and brachioradialis muscles in your forearm. They supply blood not just to the muscles but also to the lateral surface of the radius bone (one of the two bones in your forearm) and skin. Sensitivity can be maintained in the transferred tissue by including the medial and/or lateral antebrachial nerves, which are near the tissue being moved.
If bone from the forearm also needs to be transferred along with the skin and tissue, a piece of the distal radius bone (the bone near your wrist), up to 10 to 12 cm long and 40% of its circumference, can be included. Through this procedure, the palmaris longus tendon (a tendon in your forearm) may also be moved and used as a support mechanism in more complex reconstructions.
Why do People Need Radial Forearm Tissue Transfer
Free tissue transfer is a surgical procedure where tissue from one part of the body (donor site) is moved to another (recipient site) to replace damaged tissue. This procedure is often needed in the following cases:
Firstly, for composite and through and through defects in the oral cavity. This means there are defects that involve multiple layers of tissues in the mouth that need to be repaired. Here, radial forearm tissue (tissue from the forearm) is often a good choice.
Secondly, the procedure is used in near-total to total reconstruction for pharyngoesophageal defects. These are severe damages in the throat and the tube that leads from the throat to the stomach, often requiring complete rebuilding.
Thirdly, large scalp defects, where a significant portion of the skin covering the head is damaged, can also be repaired using free tissue transfer.
Lastly, surgery using free tissue transfer can be used as a salvage measure if chemoradiation (a combination of chemotherapy and radiation therapy) fails. This treatment approach is often used to treat cancer but doesn’t work for everyone. In such cases, surgery may be necessary to remove tumors and repair the damage caused by them.
When a Person Should Avoid Radial Forearm Tissue Transfer
Transferring tissue from the forearm to another area of the body, known as a “radial forearm tissue transfer,” may not be suitable for patients who do not pass a test called the Allen test. This important test checks if there is a good blood supply to the fingers when the radial artery, a major blood vessel in the arm, is blocked. The test should be done up to three times for certainty. The procedure might also not be suggested for those who have had surgery or injury to the arm that will donate the tissue.
When thinking about transferring bone and tissue (osteocutaneous tissue transfer) from the radius, one of the main bones in the forearm, it’s usually not recommended if the patient may need dental implants in the future. This is because only 40% of the radial bone should be taken and using more than that could significantly raise the risk of breaks in the radius. If possible, the arm that the patient uses less often (non-dominant arm) should be the one to donate tissue.
Equipment used for Radial Forearm Tissue Transfer
When a doctor performs surgery to remove a piece of tissue from the forearm (called a radial forearm free flap), they need specific tools to do the job effectively. These tools can vary based on the surgeon’s needs but may include special magnifying glasses (known as surgeon loupes), a set of forceps, and several different types of scissors – Mayo, Stevens, Metzenbaum, for example. They also need equipment to apply small and medium-sized clips (hemoclips) to control bleeding and a specialized kit used for microsurgeries. They would need a special machine (dermatome) that helps in obtaining a thin layer of skin (split-thickness skin graft) from another part of the body.
Additionally, they require specific materials to maintain a blood-free surgical area. These materials include a six-inch, latex-free bandage, an 18-inch air-pressure based device (pneumatic tourniquet cuff), and a special sterile roll specifically designed for surgeries. After the surgery, they would need two suction drains (10 mm each) to manage fluids and blood in the surgical area. To keep the blood vessels clean, they wash them with a solution containing a blood-thinning drug called heparin (5,000 units in 500 ml of 0.9% saline). To help with artery relaxation and prevent spasms, they would use a medication called Papaverine (60 mg in 500 ml of 0.9% sodium chloride solution) on the area surrounding the radial artery (main artery in the forearm).
During the operation, to maintain the patient’s body temperature at 99.6 F (37.6 degrees Celsius), a warming blanket is placed on the patient. This is done because a stable body temperature helps in better recovery after the surgery.
Who is needed to perform Radial Forearm Tissue Transfer?
The operation to remove the disease and reconstruct the area using a piece of tissue from the forearm is a complex process. Because of its complicated nature, it is suggested that two specially trained surgeons who are very familiar with the procedure should perform it. Having two experienced surgeons will help to lessen any potential complications and also reduce the amount of time you are under general anesthesia (this is the deep sleep you’re put in during surgery).
Other important team members include a skillful nurse, a scrub nurse (a nurse who assists surgeons inside the operating room), and an anesthesiologist (a doctor who handles the sleep medication during operations). These experts are crucial to ensure that the operation is completed smoothly and effectively.
Preparing for Radial Forearm Tissue Transfer
Before a surgery, it is very important that the doctor is aware of any past injuries or surgeries at the site from where tissue may be taken for the surgery (this area is known as the donor site). To ensure that the area has a healthy blood flow, and can heal well after the operation, a test known as the Allen test is conducted. This test involves observing how quickly the hand can refill with blood – if it takes six seconds or less, there’s enough blood flow for the surgery. It’s critical that the surgical team, anesthesia providers, and nurses all understand that no intravenous (IV) tubes or arterial lines can be placed on the forearm that’s being used as the donor site. The patient and their family should also be told that no IV lines or needles should be placed in this area.
The day of the surgery, the hairs on the forearm and the donor site are shaved to keep everything clean and to reduce the chance of complications. Once the patient is asleep under general anesthesia, they are prepared for the surgery. This includes turning the operating table and placing the arm to be used for donation at a 90-degree angle from the body. The arm and the donor site are sterilized with a special antiseptic solution (povidone-iodine or chlorhexidine), and covered with sterile towels to keep the area clean.
Lastly, a special device called a tourniquet is placed around the donor arm just above the elbow. This is used to stop blood flow to the area temporarily. After draining the arm of blood, the tourniquet is inflated just before starting the operation. This helps give the surgeon a clear view of the area while they’re working, which is essential for a successful surgery.
How is Radial Forearm Tissue Transfer performed
The procedure of harvesting a radial forearm free flap is broken down into several steps. Here’s a simplified version for you.
1. During the procedure, first of all, the doctor will gently lift the flap of skin at your forearm, moving from the side of your little finger towards the thumb, and will ensure that this is done above your arm muscle. A crucial part to remember here is not to damage the connective tissue that lies nestled between the tendons (bands joining muscle to bones) in your arm. Furthermore, the doctor won’t make an incision at the top of this skin flap at this stage.
2. Here, the doctor will keep gently lifting the skin flap until a tendon of the muscle is reached. An important part of this step is to ensure that the small vein and the branch of the nerve in this area are not damaged as this can prevent numbness in the area.
3. As the doctor continues the operation, they will tie off and safely cut the artery and the smaller veins near it, just before they travel into the hand. After this, the doctor will make a cut at the top of the skin flap and lift it in a way that helps them preserve the small nerves on the undersurface while extracting the upper layer of fat under the skin, to be used in the flap.
4. Then, the focus shifts to the top part of the flap where the skin overlying the mentioned small vein will be incised towards the crease in your elbow (antecubital fossa). The perforating veins and nerves are identified and will be included in the flap. The skin flap will be lifted off the muscle bands in the forearm while keeping the necessary vessels safe and intact.
5. Finally, the surgeon completes lifting the skin flap along with its attached vessels, and allows the blood to flow back into the hand by releasing the tourniquet. These are the final steps for harvesting the skin flap. It can keep it safe by covering it with moist towels until the operation area is prepared for accepting its transfer.
6. After this process, the donor site from where the flap was taken is closed using a skin graft from the thigh. This graft from the thigh is obtained using a surgical tool called a dermatome, to a recommended depth of about 0.018 – 0.023 inches. Then, the doctor places sponges soaked in a medicated solution over the grafted area to control bleeding. This skin graft is then used to close the area at the wrist from where the skin flap was taken. The upper part of the arm is then closed in layers after placing a drain tube.
7. Lastly, the doctor may use a special ‘bolster’ dressing over the skin graft to apply some pressure for better healing. The wrist is then put in a special brace at an angle of 45 degrees while care is taken to avoid unnecessary compression on the arm.
Possible Complications of Radial Forearm Tissue Transfer
: Apart from the general risks linked to a type of surgery called microvascular reconstruction, the most common issue with this procedure is that the skin graft, or transplant, used to close up the donor site might not heal completely. Other less common problems could include a hematoma or seroma in the forearm; these are both conditions where blood or other bodily fluids pool under the skin, causing swelling. There might also be a lack of feeling in the area covered by the superficial branch of the radial nerve, or the hand could become weak or stiff.
It’s really important for patients to be properly informed about what to expect in terms of how the donor site will look after the surgery. The skin graft will often be discolored, or a different color to the rest of the skin, for between 8 to 12 weeks after the operation. However, as the graft heals and matures, the color will start to look more natural and match the color of the skin on the rest of the forearm better.
What Else Should I Know About Radial Forearm Tissue Transfer?
The process of moving tissue from the forearm to other parts of the body, known as radial forearm tissue transfer, is a great option for patients who have large gaps or wounds in the head and neck area. This is because the tissue from the forearm is flexible, easy to access, and has a consistent structure. These features make this method a reliable choice for surgeries that involve rebuilding various parts of the body with microvascular reconstruction — a complex procedure where small blood vessels are connected to restore blood flow to the transplanted tissue.
